1
The variance of this data set is 22.611
They are 15, 16, 17, 18 & 19.
18 falls between 17 and 19.
The numbers are 17, 18, 19, 20 and 21.
It is 18 which is in between the prime numbers of 17 and 19
5
17 + 18 + 19 = 54
15
There are no such numbers. 15+16+17+18+19 = 85 and 16+17+18+19+20 = 90 Such question must be answered in terms of integers because otherwise the concept of consecutive cannot be used.
18 (All even numbers except 2 are composite.)
17, 18, 19, 20 and 21.
They are 17, 18, 19, 20 and 21.